The present invention relates to computer-based multimedia document viewing and, in particular, to a novel mechanism by which temporal annotations are added to a multimedia document.
Information presentation has changed dramatically in recent years. Dramatic increases in computational capacity of home-based computer systems and proliferation of multimedia devices such as color monitors, graphics processing cards, sound processing cards, and video capture cards has made multimedia presentation of information ubiquitous. Such multimedia presentation includes text, graphics, and streaming video and audio content. For example, a multimedia presentation of a college course lecture can include motion video and audio of a live or pre-recorded lecture and a table of contents for the lecture to assist a human viewer in following the substance of the lecture. Multimedia presentations provide large amounts of information in a dense form in which juxtaposition of text, graphics, motion video, and audio convey much more information than can be conveyed using text and/or graphics alone. Such information includes voice inflection of a speaker, sounds, non-verbal communication of a speaker, or simply a perspective provided by similar information in various forms juxtaposed in a single multimedia document.
At the same time, computers are more interconnected now than ever. Both local area and wide area networks are growing in number at a tremendous rate. In addition, the number of computers connected to the Internet, a wide area network which reaches nearly every part of the planet, is growing at a phenomenal rate. Thus, computers are increasingly sharing information with other computers, frequently across national and continental boundaries. Some communications protocols supported on the Internet, e.g., the Hypertext Transfer Protocol (HTTP) and Realtime Transport Protocol(RTP) which are used on a portion of the Internet referred to as the World Wide Web, support retrieval of multimedia documents across the Internet. Accordingly, the dense presentation of information afforded by multimedia is accessible to a tremendous number of people worldwide.
The benefits of multimedia presentation of information and of wide connectivity of computers are being used to great advantage in academia and in corporations. For example, in academia, course lectures in streaming video and audio format are made available worldwide through the World Wide Web. Any improvements in, or added functionality to, multimedia presentation of information have far reaching benefits and value to national and international exchange of information and knowledge.
One such desirable added functionality is the ability to enable collaboration in which various users can add content in the form of annotations to multimedia documents. Currently, adding content to a multimedia document or associated web pages requires write access to the multimedia document and/or associated web pages such that content can be added directly into the multimedia document. However, it is Often preferred that the content of various multimedia documents as originally authored be preserved. For example, a user or a group of users may which to add personal comments to a multimedia document such that the comments are only accessible to the user or group. The original author of the multimedia document may wish that other users can view the multimedia document without viewing the comments of the user or group and therefore prefers that the original content of the multimedia document is preserved. Such preservation typically requires denying write access to viewers of the documents. What is therefore needed is a mechanism by which viewers of multimedia documents can add annotations to such multimedia documents without granting such viewers write access to such multimedia documents.
In accordance with the present invention, a viewer of a multimedia document through use of a computer can add substantive content to the multimedia document to thereby annotate, comment upon, and augment the multimedia document even if the viewer has no write access to the multimedia document. Thus, a multimedia document becomes a basis for collaborative work. The substantive content added by the viewing user is in the form of a temporal annotation which identifies a particular relative time in temporally-dimensioned content of the multimedia document and which includes user-authored content provided by the viewing user. The temporally-dimensioned content can include, for example, animations, slide shows, motion video, and audio content. The user-authored content can include, for example, textual comments of the viewing user regarding the particular substance of the temporally-dimensioned content at the particular relative time in the multimedia document. The user-authored content can further include, for example, graphics, motion video, audio, and/or hypertext links to other multimedia documents. In addition, the temporal annotations can themselves be multimedia documents which can be augmented by other temporal annotations.
A multimedia document player recognizes an association between the temporal annotations and the multimedia document and incorporates and synchronizes display of the temporal annotations with the display of the multimedia document. Thus, display of the multimedia document includes presentation of the temporal annotations created by the user. Specifically, as temporally-dimensioned content of the multimedia document is displayed, temporal annotations are represented in the display of the multimedia document as the particular relative time represented by each temporal annotation is reached. Thus, the user-authored content becomes part of the display of the multimedia document in a temporal context. The user can select temporal annotations which satisfy various criteria for inclusion in the display of the multimedia document, e.g., temporal annotations created by a particular user or created since a particular date, for inclusion in the presentation of the multimedia document. In addition, the user can use temporal annotations to control playback of the multimedia document. Specifically, a graphical user interface of the multimedia document player enables the user to jump within the playback of a multimedia document to a particular relative time associated with a temporal annotation, Specifically, the user can select a temporal annotation from a list, and playback of the multimedia document by the multimedia document player immediately proceeds to presentation of the multimedia document such that temporally-dimensioned content is presented at the particular relative time represented by the selected temporal annotation.
The temporal annotations can be private or public. A private temporal annotation is displayed only to the specific user that created the temporal annotation when displaying the multimedia document. One user viewing the multimedia document does not see the content added by temporal annotations of another user viewing the same multimedia document. A public temporal annotation is stored in publicly accessible storage, e.g., on a shared server on the Internet, such that display of the multimedia document can include user-authored content of any temporal annotations stored in the publicly accessible memory. Such user-authored content created by other users thus becomes part of the multimedia document. General conventional access rights which control access to other computer resources, e.g., specific peripheral devices or data files stored in computer memory, can be used to control access by a user to temporal annotations created by another user. Such access rights can identify specific users and/or groups of users and can authorize specific types of access for each user or group, namely, read, write, delete, and create access.
In practice, private temporal annotations are used by a user to make personal notes and comments regarding the substantive content of a multimedia document. For example, a student can annotate a multimedia presentation of a course lecture with personal notes and links to related information. Public temporal annotations can be used by a group of viewing users to perform collaborative work. For example, a multimedia document can include motion video of a proposed video story for a news broadcast. The multimedia document can be made available to a group of people who collaborate to collectively make decisions regarding the final form of the video story. Since computer networks reach globally, the people can be distributed throughout the world and can still each review the multimedia document. When one of the collaborating people creates a public temporal annotation which is associated with a particular relative time of the temporally-dimensioned content, e.g., motion video and audio content, of the multimedia document, the public temporal annotation becomes part of the multimedia document such that subsequent viewing of the multimedia document by others of the group causes display of the added content of the public temporal annotation within a temporal context. Thus, the other collaborating people can view the content of the public temporal annotation in the temporal context of the motion video and audio content of the multimedia document and can incorporate their own comments in the form of additional public temporal annotations.
Thus, in accordance with the present invention, multimedia documents can be made living documents in that those who view multimedia documents can add to the substantive content of the multimedia documents within a temporal context. Such multimedia documents become the collective work of all who view, and choose to add to the substantive content of, those multimedia documents.